Answer:
The Amount of work is done on the box by the net force is 378 Joules.
Explanation:
Given:
A 42 N net force is applied to a box which slides horizontally across a floor.
Force = 42 N
Force applied for a displacement of 9.0 m
Displacement = 9.0 m
To Find:
Amount of work is done on the box by the net force = ?
i.e Work = ?
Solution:
When a force causes a object to move, work is being done on the object by the force. Work is the measure of energy transfer when a force (F) moves an object through a distance (d).
Formula is given by
Substituting the given values we get
∴ Work = 42 × 9.0
∴ Work = 378 N-m
or
∴ Work = 378 Joules
The Amount of work is done on the box by the net force is 378 Joules.
Answer:
The frequency of the piano string is <em>1059 Hz</em>.
Explanation:
The frequency beat (fb), 2 beats/second, is the absolute difference between the frequency of the tuning fork (1056 Hz) and the frequency of the piano string.
As the piano string gets tightened, the frequency beat becomes 3 beats/second.
Therefore,
fb =
Answer:
Constant speed: yes
Constant velocity: no
Explanation:
Let's remind the definition of speed and velocity:
- Speed is a scalar quantity, which is equal to the ratio between the distance covered (regardless of the direction) and the time taken:
- Velocity is a vector quantity, so it has both a magnitude and a direction. The magnitude is equal to the rate between the displacement of the object and the time taken, while the direction is the same as the displacement.
In this problem, we notice that:
- The speed of the car remains constant, as it is 90 km/h
- However, its direction of motion changes while the car travels round the corner: this means that the direction of the velocity is also changing, therefore velocity is not constant.